Submission #1264433

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264433		mingga	Toll (BOI17_toll)	C++20	100 / 100	83 ms	43336 KiB

toll

// Author: caption_mingle
#include "bits/stdc++.h"

using namespace std;

#define ln "\n"
#define pb push_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)(x).size())
#define ll long long
const int mod = 1e9 + 7;
const int inf = 2e9;
const int N = 50005;
int k, n, m, q;
ll f[N][20][5];



vector<pair<int, int>> g[N];

signed main() {
	cin.tie(0) -> sync_with_stdio(0);
	#define task ""
	if(fopen(task ".INP", "r")) {
		freopen(task ".INP", "r", stdin);
		freopen(task ".OUT", "w", stdout);
	}
	cin >> k >> n >> m >> q;
	for(int i = 1; i <= m; i++) {
		int a, b, t; cin >> a >> b >> t;
		g[a].pb({b, t});
	}
	for(int i = 0; i < n; i++) {
		for(int j = 0; j < 20; j++) {
			for(int t = 0; t < k; t++) {
				f[i][j][t] = inf;
 			}
		}
	}
	for(int i = 0; i < n; i++) {
		for(auto [v, w] : g[i]) {
			f[i][0][v % k] = w;
		}
	}
	for(int j = 1; (1 << j) <= n / k; j++) {
		for(int i = 0; i < n; i++) {
			for(int x1 = 0; x1 < k; x1++) {
				int bl = (i / k) + (1 << (j - 1));
				for(int x2 = 0; x2 < k; x2++) {
					if(bl * k + x2 >= n) continue;
					f[i][j][x1] = min(f[i][j][x1], f[i][j - 1][x2] + f[bl * k + x2][j - 1][x1]);
				}
			}
		}
	}
	for(int i = 1; i <= q; i++) {
		int a, b; cin >> a >> b;
		int range = (b / k) - (a / k);
		vector<vector<ll>> mn(2, vector<ll>(k, inf));
		mn[0][a % k] = 0;
		int bl = a / k;
		for(int j = 0; (1 << j) <= range; j++) {
			if(range >> j & 1) {
				for(int x1 = 0; x1 < k; x1++) {
					for(int x2 = 0; x2 < k; x2++) {
						if(bl * k + x2 >= n) continue;
						mn[1][x1] = min(mn[1][x1], mn[0][x2] + f[bl * k + x2][j][x1]);
					}
				}
				bl += (1 << j);
				mn[0] = mn[1];
				mn[1] = vector<ll>(k, inf);
			}
		}
		if(mn[0][b % k] >= (int)inf) cout << -1;
		else cout << mn[0][b % k];
		cout << ln;
	}
    cerr << "\nTime: " << clock() * 1000 / CLOCKS_PER_SEC;
}

Compilation message (stderr)

toll.cpp: In function 'int main()':
toll.cpp:27:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |                 freopen(task ".INP", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
toll.cpp:28:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |                 freopen(task ".OUT", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 8 / 8
• Subtask 4: 31 / 31
• Subtask 5: 44 / 44